1. Field of the Invention
The present invention relates to a connector, and in particular to a connector which is applicable to radio frequency (RF) signal transmission.
2. Description of Related Art
With the development of science and technology, the dimensions of modern electronic products are reduced continuously. Accordingly, the dimensions of electronic elements (such as connectors) within the electronic products have also become more compact so as to correspond to the smaller electronic products.
Please refer to FIG. 1, which shows a small connector for transmitting RF signals. Such a connector can be inserted by a docking plug (not shown), thereby transmitting RF signals. The connector includes a grounding terminal 10a, a signal terminal 20a and an insulating casing 30a. The grounding terminal 10a has an annular body 11a. The signal terminal 20a has a substrate 21a. One end of the substrate 21a is provided with a soldering portion 22a. Near the other end of the substrate 21a, the signal terminal 20a is formed with a hollow cylindrical contacting portion 23a by means of a draw-forming process. The contacting portion 23a is disposed in the center of the annular body 11a. The insulating casing 30a is used to cover the grounding terminal 10a and the signal terminal 20a. The soldering portion 22a extends outside the insulating casing 30a. 
However, when the above conventional connector is in use, the signal terminal 20a may become disconnected from the insulating casing 30a while the docking plug is inserted into or pulled out of the connector, because of the unsteady connection between the substrate 21a of the signal terminal 20a and the insulating casing 30a. Furthermore, since the contacting portion 23a of the signal terminal 20a is made by means of a draw-forming process, the roundness is poor, so that the signal transmission is unstable.
Consequently, because of the above limitation resulting from the technical design of prior art, the inventor strives via real world experience and academic research to develop the present invention, which can effectively improve the limitations described above.